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for example, they were told to indicate which one of the three pictures was the "table." Performance was high, with mean accuracy levels of close to

90 percent correct. Thus, the removal of naming from the Pictures for the Blind

163 recognition task greatly improved performance in the interpretation of haptic pictures. These results mean that part of the difficulty that subjects sometimes experience with tangible pictures may derive from a lack of familiarity with them, rather than with any intrinsic limitations in haptics, per se. A more recent study examined picture matching, and completely eliminated the problem of semantic memory from the task (Heller, 2002;

Heller et al., 2002a). Figure

1 shows the raised-line pictures used for this experiment. Subjects felt a target picture, and then felt four picture choices. The task was a simple match to sample. Subjects were timed as they felt the target and four picture choices, but were told to try for accuracy. The participants included blindfolded sighted subjects, late-blind subjects (LB), congenitally blind (CB) subjects and others with very low vision (VLV). Almost all of the VLV subjects were Braille readers and used a long cane for mobility. They tended to refer to themselves as blind, since they had no remaining pattern vision, or it was minimal. Most of these persons claimed that they could not see the close hand motion, but a few said that they could. In contrast to the blind subjects, these VLV individuals were able to see the direction of a strong light source (e.g., from a lantern). Performance was near ceiling. In order, mean number correct out of 15, for the VLV, LB, CB and sighted subjects were 14.9, 13.9, 13.7, and 13.3. Performance was exceptional for the VLV subjects at 99.3% correct, but the CB subjects also had over 91% correct. An ANOVA on number correct yielded a nonsignificant effect of visual status (p >0.2), and the interaction between visual status and type of picture was also nonsignificant (F